Justin Thomas equalled the course record to take a three-shot lead after the opening round at the RBC Heritage.
Thomas made 11 birdies in a 10-under-par 61 at Harbour Town Golf Links in South Carolina.
The 31-year-old American, who is seeking his first victory since winning his second major at the 2022 US PGA Championship, leads compatriots Russell Henley and world number one Scottie Scheffler.
Former US Open champion Wyndham Clark is one shot further back, while England’s Matt Fitzpatrick is among a group on five under after an opening 66.
Justin Rose is in a tie for 10th after hitting 67 in his first round since losing to Rory McIlroy in a play-off at the Masters.
Thomas set the pace with six birdies on the front nine, before he recovered from a bogey on the 10th by hitting five birdies in six holes on the back nine.
“I feel like I didn’t do anything crazy,” said Thomas.
“I just drove the ball well, which is very, very important out here, and I felt like it was just one of those days I put the ball in a spot that I had a lot of good numbers.”